The present invention relates to an electronic gaming machine and in a particular an electronic gaming machine using a base game and a feature game. The invention has been developed primarily for use as an electronic gaming machine and will be described hereinafter by reference to this application.
The following discussion of the prior art is intended to present the invention in an appropriate technical context and allow its advantages to be properly appreciated. Unless clearly indicated to the contrary, however, reference to any prior art in this specification should not be construed as an express or implied admission that such art is widely known or forms part of common general knowledge in the field.
Conventional gaming machines typically involve awarding prizes to a player according to predetermined combinations of game symbols that appear on an array of game squares displayed on a screen, typically organised into three rows and five columns (a 5×3 array). Other arrays, such as a 3×3 or 4×3, may be used. Each gaming machine randomly selects the game symbols that appear on the array, each column of the array being a “reel”.
In an electronic gaming machine, the mechanical reels are replaced with video images of the reels, which are displayed on a video display screen. The electronic gaming machine has an internal electronic game controller, typically a computer, that controls the display of images on the video display screen so that the reels are visibly spun on the screen to simulate a physical reel of a traditional gaming machine. Electronic gaming machines are also more versatile in presenting game information, varying the probabilities for a player to win a prize and varying the type of game that is played.
Bonus or “feature” games may also be provided by an electronic gaming machine in addition to a base or main game. Typically feature games use the same set of reels as the main game and are limited to a set of free games operated under a single set of rules. This means that the feature game is restricted by the same set of rules, and so there is no variation in the play of the feature game.
Also, electronic gaming machines can offer one or more bonus prizes to the player during play of the game. The most common type of bonus prize that is awarded by the electronic gaming machine is a jackpot prize, the main example of which is a progressive jackpot prize.
This standard structure to game play and bonus prizes limits the variation in the play of the electronic gaming machine. Consequently, it is difficult to retain player interest because there is no apparent incentive for the player to continue playing the same electronic gaming machine once the player becomes familiar with the feature game, the main game and any bonus prizes. Also, it is difficult to retain player interest since there is little differentiation between gaming machines in terms of the main and feature games that are played.
It is an object of the present invention to overcome or substantially ameliorate one or more of the disadvantages of prior art, or at least to provide a useful alternative.